This invention relates generally to a cage for use with a multiple dosage feeder for an animal cage, which selectively exposes one of a plurality of precise dosages of food or other substances to an animal within the cage while covering the remaining dosages, and more particularly to a door and lock mechanism capable of receiving the multiple dosage feeder.
Animals used in laboratory experiments and housed in cages must be supplied with a nutritionally adequate amount of diet to allow for normal growth and development, as well as to permit such animals to ingest various ingredients in the diet for experimental purposes. While it is often not difficult to encourage an animal to eat, many experimental animals, such as rats and mice, tend to overeat, become obese and eventually develop obesity-related diseases. Unfortunately, such abnormalities in the animal's metabolism may interfere with the experimental end point being studied in an experiment. Accordingly, it is important to administer only a measured dosage of food to such animals to prevent such artifacts and experimental errors. Additionally, in certain experiments, such as those involving toxicological, preclinical testing of pharmaceutical agents and/or nutritional studies, it is important to quantitate the amount of diet or test ingredient agents ingested by an animal. Therefore, it is important to administer only a measured dosage of diet at predetermined intervals to control the intake of diet and the outcome of the experiment.
Heretofore, the administration of measured dosages of food to laboratory animals in cages has been accomplished manually for each feeding interval and for each cage. The manual method of administering measured dosages of food suffers from several drawbacks. The process is slow and cumbersome, requires more frequent handling of the equipment and animals by laboratory personnel and increases the likelihood of error in recording the dosage of food. Additionally, the currently available models of containers have a wide opening and are suitable either to place on the floor of a cage or to affix to a clamp located to the inside of the front frame of the cage. As a result, the laboratory animals are usually found to spill the diet from the container either during the feeding or by playing with the diet especially when it is in the powder form. Such spillage of diet is yet another means of introducing error in recording the dosage of food and/or test agent.
Accordingly, it is desired to provide a multiple dosage feeder for an animal cage which selectively provides one of a plurality of dosages of food to an animal within a cage in a structure which limits the animal to eating a single dosage at a feeding interval, reduces the number of steps and time required to administer measured dosages of food to each cage, indicates whether a particular dosage has been administered, eliminates the necessity of opening the cage to administer the measured dosages of food, and reduces the amount of diet spillage. It is further desired to provide a multiple dosage feeder which can be placed into a housing member which in turn can be placed into and removed from the cage through an opening in the cage.